Struct ReQueryObservable 

pub struct ReQueryObservable { /* private fields */ }

A re-query based observable that re-executes the query on each change. This leverages the query optimizer and indexes for optimal performance. The physical plan is cached to avoid repeated optimization overhead.

Implementations

impl ReQueryObservable

pub fn new( physical_plan: PhysicalPlan, cache: Rc<RefCell<TableCache>>, initial_result: Vec<Rc<Row>>, ) -> Self

Creates a new re-query observable with a pre-compiled physical plan.

pub fn result(&self) -> &[Rc<Row>]

Returns the current result.

pub fn len(&self) -> usize

Returns the number of rows.

pub fn is_empty(&self) -> bool

Returns true if empty.

pub fn subscribe<F: Fn(&[Rc<Row>]) + 'static>(&mut self, callback: F) -> usize

Subscribes to changes.

pub fn unsubscribe(&mut self, id: usize) -> bool

Unsubscribes by ID.

pub fn subscription_count(&self) -> usize

Returns subscription count.

pub fn on_change(&mut self, changed_ids: &HashSet<u64>)

Called when the table changes - re-executes the cached physical plan. Only notifies subscribers if the result actually changed. Skips re-query entirely if there are no subscribers.

changed_ids contains the row IDs that were modified - used to optimize comparison by only checking these rows when the result set size is unchanged.